Definitely sounds like power compact (PC) lights. I would change the bulbs and plan on changing them at least once a year in order to keep them from shifting spectrum and losing output.
Great information on this tank. :clap2: I would suggest the same as above, water change, testing, skimmer, and really consider taking you HOB filter off. Typically SWT's don't need them, they are used for FWT's. Good luck and don't stop asking questions. This site has a world of knowledge.
I agree with the info above, by a couple 5 gallon water jugs at Walmart and go to your local fish store and buy Rodi water. It's usually 10-25 cents a gallon. Hassle to haul back and forth but worth it. Scrap the filters and buy a protein skimmer ASAP check Craig's list or eBay and or LFS for a used one. Bulb change is a must since you don't know how old they are. As soon as possible look I to a Rodi filter. I got mine from bulk reef supply for $160 and it's worth every penny ! If that's red slime or cyno bacteria you can use Boyd's chemi-clean but follow directions to the tee. It is safe for corals, fish, inverts but you have to provide some air bubbles and do a 20% water change 48 hours after. It will wipe out the red cyno in a day or two
This hobby is very rewarding once you figure out all the problems, next you will be asking how to rid your tank of Aiptasia !
A phosphate removing media is definitely a option like a Gfo reactor also bulk reef supply carries some good options, but first I would try the other suggestions I have recently started doing weekly 15% water changes and have done them for about 5 weeks and I don't have issues like I did before, I also had hair algae, red cyno
Did a 15 percent water change with ro/di water. And bulb is on order. As soon as I can get a protein skimmer I will. Thanks again. As soon as tank clears up ill post another pic.
Ya Laurieo if you have a skimmer you don't need any other filters really besides live rock, some like to use mechanical filtration like a filter sock but a skimmer is all you really need at some point a carbon reactor would be a nice addition as well